Measurement of the amount of one or more catecholamine hormones, any of a group of amines composed of a pyrocatechol molecule and the aliphatic portion of an amine that have important physiological effects as hormones and usually also as neurotransmitters, in a specified sample of blood, the fluid that circulates through the heart, arteries, capillaries and veins carrying nutrients and oxygen to the body tissues and metabolites away from them. A hormone is a substance produced in one part or organ of the body that initiates or regulates the activity of an organ or a group of cells in another part of the body.